Gaya APA

Billstein, R., Shlomo, I, L. (). Problem solving approach to mathematics for elemantary school teachers . California:: California: Benjamin/Cummings; 1990.

Gaya MLA

Billstein, Rick., Shlomo, I., Libeskind,. "Problem solving approach to mathematics for elemantary school teachers". California:: California: Benjamin/Cummings; 1990, . Text.